Respirators are used to enable the user of the respirator to spend a long time in an environment in which the air contains toxic substances. Respirators are used with and without a closed breathing air circuit. If the respirator has a closed breathing air circuit, CO2 is removed from the expired air and oxygen is added from a pressurized gas cylinder acting as an oxygen cylinder. The oxygen reserve of the oxygen cylinder is, for example, under a pressure of 300 bar in this case. The respirator has a carrying tray, to which the components of the respirator are fastened. Due to the high pressure of the oxygen in the oxygen cylinder, a pressure reducer is necessary. The oxygen cylinder, which has a circular cross section, is fastened as a container wall to the respirator with a pressurized gas cylinder holder.
The pressurized gas cylinder holder has a holding part made of plastic and at least one tightening strap for fastening the pressurized gas cylinder. The holding part has a partly arc-shaped cross section and the pressurized gas cylinder is placed on this part of the holding part and then fastened with a tightening strap. It may in this case be necessary to fasten oxygen cylinders with a different external diameter to the pressurized gas cylinder holder. The pressurized gas cylinder has a longitudinal axis and if the external diameter of the pressurized gas cylinder is different, this causes the centric longitudinal axis of the pressurized gas cylinder not to be aligned correspondingly any longer with the pressure reducer or with a 90° pressurized gas elbow in case of an external diameter that is greater than the external diameter for which the holding part is designed. As a result, the pressurized gas cylinder cannot be connected any longer to the respirator or to the pressurized gas cylinder holder of the respirator, because the ports on the pressurized gas cylinder for removing oxygen are no longer aligned with the ports of the pressure reducer.
DE 729 555 A shows a holder for pressurized gas cylinders with a tightening strap, which is fastened to the support body of the pressurized gas cylinder, is led around the body of the cylinder and is held together with a manual closing device, wherein the securing means, which hold the tightening strap at the support body of the pressurized gas cylinder, and the closing parts, which connect the two tightening halves to one another, are hung themselves detachably into holding means, especially recesses of the tightening strap, which occur repeatedly in the longitudinal direction of the tightening strap.
WO 01/91857 A1 shows a cylinder support for pressurized gas cylinders, against which one or more pressurized gas cylinders are pressed by means of a tightening strap after establishing the connections between the high-pressure connecting branch and the pressure reducer. The cylinder support has sliding inserts, which protrude from the surface of the cylinder support in the direction of each pressurized gas cylinder, so that each filled pressurized gas cylinder is mounted on them in the unbraced state and can be slidingly moved, and the sliding inserts can be recessed into the cylinder support under the action of the force of the tightening strap on the pressurized gas cylinder and hence at the same time under the action of the force acting on the sliding inserts.